The recent emphasis of health and its association with food has increased the use of steam cooking because of its unique capabilities. The flavor of many foods is retained when cooked with steam and is sometimes enhanced. Nutrients, such as vitamins, minerals, etc., are less prone to degradation when foods are cooked with steam. The appearance, texture, and color, especially of delicate foods such as vegetables, remain pleasing when cooked with steam. Of concern to the commerical food sector is time; applications of steam to commercial cooking can result in faster food preparation.
For browning of some foods, such as roasts for example, it is sometimes advantageous to maintain drier food surfaces at high temperatures by the use of dry air convection heating.
Oftentimes a combination of steam and convection heating is desired U.S. Pat. No. 4,700,685 to Miller issued Oct. 20, 1987, discloses an oven for cooking foodstuffs with either steam or convection hot air. A slinger cup atomizes water by centrifugal force which flows over an electrical heater to produce steam. The temperature of the cooking cavity is measured and used to control the electric heater.
European Patent No. EP277888 to Violi published Aug. 10, 1988, appears to disclose an oven that uses a small boiler to generate steam which is mixed with combustion gasses from a gas burner and introduced into the cooking chamber.
U.S. Pat. No. 4,722,321 to Meister issued Feb. 2, 1988, discloses an oven with a boiler for providing steam and a heating coil surrounding a blower for providing heated convection gases. A temperature sensor is positioned in a bypass line to a discharge pipe.